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高频雷达机动目标的时频图像处理方法研究 被引量:3
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作者 雷志勇 黄银河 《中国电子科学研究院学报》 2009年第2期197-201,共5页
高频雷达机动目标检测实为复杂外部环境和强地海杂波下的非平稳弱信号处理,针对非平稳特征提出了基于时频分析和图像处理的方法。首先应用时频分析方法得到机动目标的时频谱,进而在时频谱上进行频率维的恒虚警检测并形成目标像、在时间... 高频雷达机动目标检测实为复杂外部环境和强地海杂波下的非平稳弱信号处理,针对非平稳特征提出了基于时频分析和图像处理的方法。首先应用时频分析方法得到机动目标的时频谱,进而在时频谱上进行频率维的恒虚警检测并形成目标像、在时间维应用区域生长技术提取目标的速度时变脊线。时频图像处理方法经频率维和时间维的多级处理、在保证系统检测性能的情况下可精确提取机动目标的速度时变信息。实测数据的处理验证了其有效性。 展开更多
关键词 高频雷达 机动目标检测 时频图像处理 区域生长技术 脊线提取
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基于时频图像处理的宽带特定信号检测方法 被引量:3
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作者 孙伟 彭华 +2 位作者 李天昀 许漫坤 陈洋 《信息工程大学学报》 2020年第5期545-551,共7页
针对短波超短波宽频带环境下的特定信号检测问题,传统的处理方法主要分为以人工参与为主的宽带侦察和宽带检测、窄带处理两种,存在侦察效率低、自动化处理水平不高等问题。针对此问题,提出了一种基于时频图模板匹配和峰值搜索的宽带特... 针对短波超短波宽频带环境下的特定信号检测问题,传统的处理方法主要分为以人工参与为主的宽带侦察和宽带检测、窄带处理两种,存在侦察效率低、自动化处理水平不高等问题。针对此问题,提出了一种基于时频图模板匹配和峰值搜索的宽带特定信号检测方法,通过预先构建特定信号的时频图模板,逐点滑动求时频图模板与宽带数据时频图的相关系数,对相关系数进行阈值判决和峰值搜索,完成特定信号的初步检测。该方法直接在宽带接收数据中进行特定信号的搜索检测,不仅能提高特定信号检测速度,还能节约窄带接收机资源。通过仿真实验,验证了该方法的有效性。 展开更多
关键词 时频图像处理 模板匹配 特定信号检测 宽带数据预处理
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Fast Motion Estimation Algorithm with Edge Alignment for H.264 Encoder
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作者 Rastislav Adamek Gabriela Andrejkova 《Computer Technology and Application》 2013年第7期341-345,共5页
Image sequences processing and video encoding are extremely time consuming problems. The time complexity of them depends on image contents. This paper presents an estimation of a block motion method for video coding w... Image sequences processing and video encoding are extremely time consuming problems. The time complexity of them depends on image contents. This paper presents an estimation of a block motion method for video coding with edge alignment. This method uses blocks of size 4 × 4 and its basic idea is to find motion vector using the edge position in each video coding block. The method finds the motion vectors more accurately and faster than any known classical method that calculates all the possibilities. Our presented algorithm is compared with known classical algorithms using the evaluation function of the peak signal-to-noise ratio. For comparison of the methods we are using parameters such as time, CPU usage, and size of compressed data. The comparison is made on benchmark data in color format YUV. Results of our proposed method are comparable and in some cases better than results of standard classical algorithms. 展开更多
关键词 Codec H.264 ENCODER edge detection EVO (Enabling Virtual Organizations) conference system.
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LPI radar signal detection based on radial integration of Choi-Williams time-frequency image 被引量:26
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作者 Yongjian Liu Peng Xiao +1 位作者 Hongchao Wu Weihua Xiao 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第5期973-981,共9页
This paper mainly revolves the time-frequency image of low probability of intercept(LPI) radar signals and carries out research work on image features selection and extraction and recognition. Since Choi-Williams dist... This paper mainly revolves the time-frequency image of low probability of intercept(LPI) radar signals and carries out research work on image features selection and extraction and recognition. Since Choi-Williams distribution(CWD) uses the exponential kernel of bilinear generalized class of time-frequency distribution, it has an excellent time-frequency aggregation. And it is suitable for detecting LPI radar signals in a low signal-to-noise ratio(SNR) condition. A radial integration method based on the integral rotating factor is proposed to detect LPI radar signals when the signals' time-frequency image is obtained. First, the digital image processing method is used to preprocess the LPI radar signals' time-frequency images after CWD transformation; then, the radial integration method based on the integral rotating factor is used to detect LPI radar signals in the binary images. The analytic results of real data show that the method has a good performance on detecting LPI radar signals in a low SNR condition. Additionally,the method is simple and takes less logic resources and has the potential of real-time detection of LPI radar signals. 展开更多
关键词 low probability of intercept (LPI) integral rotating fac-tor signal detection image processing
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